Arduino IDE v2 - Port grayed out

[micha610]

Hi, I got the same issue like some of you. I switched to Fedora 41 and tried everything to get Arduino v2 working and here’s what I did:

1. added User to dialout group: sudo usermod -aG dialout $USER
2. created a UDEV-rule for ESP32: echo 'SUBSYSTEM=="tty", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", GROUP="dialout", MODE="0660"' | sudo tee /etc/udev/rules.d/99-esp32.rules
3. apply new UDEV-rule + reloaded: sudo udevadm control --reload + sudo udevadm trigger
4. checked if ESP32 is detected by system: Bus 001 Device 004: ID 10c4:ea60 Silicon Labs CP210x UART Bridge
5. checked Port Permissions for /dev/ttyUSB0: crw-rw----. 1 root dialout 188, 0 2. Feb 15:05 /dev/ttyUSB0
6. confirmed that my user is in dialout group: wheel dialout

Disclaimer: I'm using a cable which worked on my windows machine, so it can't be the issue. I also tried my Arduino MEGA 2560 which works perfectly on windows, too.

Notes:
-Operating System: Fedora 41.
-Arduino IDE v2 Version: 2.3.4
-Hardware: ESP32 with CP210x

[sterretje]

1. Disconnect the board.
2. Run dmesg -w.
   • The application does not close.
   • Press <Enter> a few times so you can clearly notice the new output for the next step.
3. Connect the board.
   • Observe the changes; anything indicating problems?
4. Close dmesg using <ctrl>C.

[micha610]

nope, I got no issues. Here you can see the output:
[ 2788.209738] usb 1-2: new full-speed USB device number 4 using xhci_hcd
[ 2788.353219] usb 1-2: New USB device found, idVendor=10c4, idProduct=ea60, bcdDevice= 1.00
[ 2788.353227] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2788.353231] usb 1-2: Product: CP2102 USB to UART Bridge Controller
[ 2788.353234] usb 1-2: Manufacturer: Silicon Labs
[ 2788.353236] usb 1-2: SerialNumber: 0001
[ 2788.386783] usbcore: registered new interface driver cp210x
[ 2788.386796] usbserial: USB Serial support registered for cp210x
[ 2788.386831] cp210x 1-2:1.0: cp210x converter detected
[ 2788.391348] usb 1-2: cp210x converter now attached to ttyUSB0

Thanks for quick reply

[sterretje]

Sorry, in that case I do not know.

[sonofcy]

My suspicion is that Fedora added another permissions setting (not sure if worded right) I would find the Fedora forum and ask over there what settings are needed to get read/write access.

[sterretje]

Check this reply for use of the serial discovery tool: IDE loses track of CP210x port - #4 by ptillisch. Maybe it helps.

There should be official documentation but I could not immediately find it on the web. I did find GitHub - arduino/serial-discovery: An Arduino IDE pluggable-discovery for Serial ports and you can read the readme.

[micha610]

You were right.
The problem was related to the Flatpak installation of Arduino IDE via Software Store. I found out that Flatpak runs applications in a sandboxed environment, which could restrict access to system resources by default (including USB/serial ports). Even with correct UDEV rules and user permissions set up, the Flatpak version couldn't access these ports.

Solution: I just downloaded the Arduino IDE directly from the official website (zip file) instead of using the Flatpak version, and the ports are now properly detected.

[micha610]

Thanks for the help

[micha610]

If someone has the same issue as me, here is an easy solution for the Flatpak version.
You only need to install Flatseal from the store and activate device=all. That's it!